During mucosal inflammation, such as in models of inflammatory bowel disease provoked by dextran sodium sulfate (DSS), trinitrobenzine sulfonic acid and oxazolone painting, both heterophilic ligation of CEACAM1 with antibodies or homophilic ligation by soluble recombinant CEACAM1-Fc fusion proteins inhibits mixed lymphocyte reactions in vitro, and hapten-mediated colitis in vivo, and is associated with inhibition of the production of proinflammatory Th1 cytokines via T-bet signaling, but not STAT4-promoted Th2 T cell differentiation and signaling [172,173,184,185,186]. Here, CEACAM1 is linked to colitis.